The field of the invention pertains to three-dimensional puzzles and, in particular, to spherical puzzles having interlocking parts.
An early example of a solid spherical puzzle is disclosed in U.S. Pat. No. 766,444 wherein a plurality of prismatic pieces form the puzzle. U.S. Pat. No. 1,546,024 also discloses prismatic pieces that interlock to form the solid sphere of the puzzle. A plurality of planar pieces interlock to form a solid spherical puzzle in U.S. Pat. No. 2,034,830. In U.S. Pat. No. 4,889,340 and U.S. Pat. No. 5,452,895, the exterior pieces move on tracks or rails about a substantially solid core. Likewise, in U.S. Pat. No. 4,377,286, U.S. Pat. No. 4,378,117 and international application PCT/AT81/00010, the exterior pieces move on interior mechanisms.
Hollow spherical puzzles are also known. U.S. Pat. No. 4,441,715 illustrates a hollow spherical puzzle wherein the pieces comprise sectors truncated by the hollow interior. In U.S. Pat. No. 4,522,401 and U.S. Pat. No. 5,114,148, the exterior pieces move on tracks about a hollow or solid core. Most of the above patents disclose geometrically and mechanically complicated mechanisms to guide the puzzle pieces. Moreover, in most of these patents the pieces always remain interconnected and are not disconnected in operating the puzzle.
Puzzles where the pieces are purposely separable are shown in U.S. Pat. No. 766,444 and U.S. Pat. No. 1,546,024 where the solid puzzles comprise prismatic pieces. Hollow puzzles where the pieces are all separable are shown in U.S. Pat. No. 3,578,331. These pieces snap or dovetail together to form the hollow puzzle.
The new puzzle comprises a solid sphere with the external appearance of a golf ball of modern construction. A series of curving cuts through the sphere separate the sphere into a plurality of separate pieces wherein the cuts form complementary pairs of surfaces among the separate pieces. Proper assembly of the pieces solves the puzzle and restores the golf ball appearance of the puzzle. The curving cuts form interlocks between the pairs of complementary surfaces whereby, once assembled, the sphere will be retained together in three dimensions in a similar manner as two-dimensional puzzle pieces are retained together. The curving cuts at the surface of the puzzle sphere resemble two-dimensional puzzle cuts in the preferred embodiment and permit the puzzle to be very economically manufactured with simple curvatures. In the preferred embodiment, the puzzle comprises eight pieces that can be slid together; however, the puzzle can be formed with more pieces for added complexity and more challenge to slide the pieces together in the proper order.